Ex 3.1, 2How many diagonals does each of the following have?(a) A convex quadrilateralDiagonal is a line joining two non-consecutive vertices of a Polygon
ABCD is a Convex quadrilateral as its diagonal is in the interior.
It has 2 diagonals - AC and BD
Ex 3.1, 2How many diagonals does each of the following have?(b) A regular hexagon
Diagonal is a line joining two non-consecutive vertices of a Polygon
ABCDEF is a regular hexagon.
AC, AD, AE
BF, BE, BD
CA, CF, CE
DB, DA, DF
EA, EB, EC
FB, FC, FD
Thus, Regular Hexagon has 9 diagonals
AE, AD, AC, BF, BE, BD, CF, CE, DF
Ex 3.1, 2How many diagonals does each of the following have?(c) A triangleDiagonal is a line joining two non-consecutive vertices of a Polygon
ABC is a triangle
It has 0 diagonals.

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